1. Technical Field
The present invention relates to a vehicle periphery monitoring device, vehicle, vehicle periphery monitoring program, and vehicle periphery monitoring method which monitors a periphery of a vehicle by detecting an object present in the periphery of the vehicle, from an acquired image of the periphery of the vehicle by a camera mounted on the vehicle.
2. Description of the Related Art
There is known a vehicle periphery monitoring device which detects an object in a periphery of a vehicle from an acquired image of the periphery of the vehicle by a camera mounted on the vehicle, calculates a relative position and relative velocity of the object in real space and the vehicle, and determines a possibility of contact between the vehicle and the object within a predetermined time (for example, refer to Japanese Patent Laid-Open No. 2001-6096).
Further, in order to identify a type of the object (human being, vehicle, large animal, and the like), a process of extracting a shape (area, outline, horizontal to vertical ratio, and the like) of an image portion in a binarized image which is obtained by binarizing a multiple-valued image obtained by the camera is carried out (for example, Japanese Patent Laid-Open No. H8-313632).
In the device disclosed in Japanese Patent Laid-Open No. H8-313632, a ratio between a width between a minimum value and a maximum value of an edge coordinate in the horizontal direction and a width between a minimum value and a maximum value of the edge coordinate in the vertical direction of a window circling the image portion in the binarized image is calculated as a horizontal to vertical ratio R, and whether or not the object in real space corresponding to the image portion is a human being is determined on the basis of the horizontal to vertical ratio R.
However, in the case of determining whether or not the object is a human being on the basis of the width between edges, there is an inconvenience that the width of the image portion of the object is not properly calculated, when image portions of a plurality of objects are included in the window. As such, there is an inconvenience that the identification accuracy of the type of the object is reduced.